Understanding the rock slope stability along Malshej Ghat, India, using rock mass characterisation and block shape classification techniques

Malshej Ghat is one of the busiest transport corridors in Maharashtra. It is highly prone to landslides, as the region receives heavy precipitation and steep slopes along the road section. This manuscript focuses on the applicability and reliability of block size and shape classification techniques in the assessment of the stability of the road-cut rock slopes. Structurally weak zones extending along and across the road section are identified as a lineament, and accordingly, slopes are chosen for in-depth analysis. Kinematic analysis signifies that wedge failure is observed to be the most common type of failure, while planar and toppling failures are observed at places. The rock blocks which are produced as a result of the intersection of different joint sets are mainly cubic, cubic-elongated and elongated in shape, whereas platy, platy-cubic and elongated-platy blocks are very less in proportion. Volume and surface area of rock blocks play a vital role in the movement of the blocks. The rock mass is observed to be nearly poor to fair in quality; however, the numerical simulation shows that the slopes MRS-1, MRS-5, and MRS-7 are critically stable.